You're about to go inside one of the ugliest houses in the country. At least from a real sale perspective. On the market for a staggering amount of money, it may stay there until someone just as eccentric as its original owner comes along. So with the housing market in an uptick, how do you make sure your own home doesn't become unsellable? Here's Rebecca Jarvis with tonight's reality check. Staircase railings that seem more than a little out of place. A bedroom that would make a caveman claustrophobic. And of course, all those lions. Welcome to the million dollar mansion that might just be America's most unsellable house. So this is the Kessler estate. It's 10 degrees below zero and there's a bunch of dolphins out front and they're covered in snow. Meet Ryan sander, listing agent on this sprawling mansion. Consider this a cautionary tale in the new hot real estate market. Basically we've got five structures. We' got the main house. We've got the guest house. We gooe've got the pool house, the ballroom conference center an an apartment that also houses additional guests. Reporter: Sanders know there are cardinal rules. First and foremost, you never want your home to be the most expensive one on the block. That's just the first of many rules being shattered here at the Kessler compound in Indianapolis. The asking price? We realtors like to say $1,295,000, which really is $1.3 million. Rounding snup. Ma Making it the costliest house in the entire zip code. The average house is $150,000. This is about ten times. From the bedrooms. This is a room almost entirely of stone. I feel like we're in the cave. This room would be like the party place down here. This room is good for a cocktail, a hand of black jack, then it's time to get into the hot tub. And the formal dining room. We've taken a trip to the orient. As you see, the formal dining room has a hint of asian influence. With a hint of circus mirrors. . Reporter: There's really no playing footsies under the table here. I'm blown away. This is definitely the most original house I've seen with the housing market making a serious recovery, more and more Americans are looking to sell. So to guide us through the do's and don'ts, we went to an expert from bravo's million dollar listing. This is, as we like to say in real estate, unique. Or one of a kind. This is definitely one of a kind. Wow. This is like a dungeon room with beds in it. At a 1 to 10, this is probably one of the worst houses I've ever seen. He's used to selling red hot luxury properties like this $5.5 million pad in the Hollywood hills. Check out this view. This view in itself is worth $2 million. Reporter: But he says any house can fall victim into overly specific design details. And that can spell doom when it comes time to resell. I see mistakes made in houses built all day long. As much as he tried, josh couldn't sell this house in Bel Air, shaped strangely like a boat. Not only is it shaped as a ship, but it probably needs about $1348 worth of upgrades. It looks like the freaking love boat in here. This thing is straight out of the '80s. This is a tough sell, man. You talk about a unique buyer. How many people do you know are looking for a ship? The more specific your house is, the more difficult to sell your house. Indiana house. Reporter: Anna spends her day poring over real estate listings, looking for the standouts. What's hideous about this one? It's got a rotunda with pink metallic hues. Oh, wow. This is the Las Vegas one. It's sort of as if you wouldn't need to leave your own home in order to get the vibe you would at the, you know, the venetian. Just put a roulette wheel right there. Right behind the bar, I think. Reporter: Back at our baffling Indianapolis mega mansion -- I love that there's railings all around this, but there's no railings going up the stairs. Great Lites coming through on the place. Reporter: Even the listing agent is confused by some of the rooms. Here you have your side room. Your salon. I'm not real sure what that room is used for. Reporter: How many rooms do you think you' said I'll not really sure what that room is used for in this house? I think it just depends on the individual person and what they want to use the room for. Reporter: This isn't available anywhere else. This is the only place where you can get this. So I have to imagine that whoever is going to come here and buy this is a little bit eccentric, has some money and wants to live in Indianapolis. And you have to put all of those things together in order to make it work. But this was all part of a 20-year construction project taken on by the estate's original owner. A convicted pimp turned construction magnate. What do you think he was going for? Do you think he had a vision of what all of this collectively would be? I just don't think he cared what people think. Reporter: In fact, this house is so ugly. Oh, look, I'm in a fish tank. It's become a local legend. Do you pass the Kessler estate on the way to work? At times. Yes. It's incredible. Reporter: If you're rich enough to build a mansion like this -- oh, cool. Maybe you're not too worried about resale value. Imagine you just bought this house. But for the rest of us -- For most of the people in this country, their house is their biggest investment in their life. You want to make sure that investment is going to make you money when you sell that house. Reporter: Rule number one -- keep it simple. You've got to keep a house one particular style. If you're going modern, stick to it the whole way through the house. Rule number two, landscaping is key. You've got to work on the curb appeal. The first thing you see is rock frontage of extra rocks all over the land. It's horrible. Reporter: Rule number three -- don't make it personal. Make it as unspecific as possible. Neutral color, take out all the personal stuff throughout the house except the house in general is personal. So at that point, I don't know, maybe take a bulldozer to it. Reporter: This isn't going to be easy to sell. Well, I think there's challenges for sure. Reporter: Challenges. That's putting it lightly. Well, I think as a realtor, though, you know, do you always want the easily necessarily sale? Or do you want to maybe work a little harder and have the challenges of something like this. Are you ready for Indianapolis million dollar listing? I think I could hand the ill for sure. Reporter: I'm Rebecca Jarvis from Indianapolis.

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